A photoresistor, also known as a light-dependent resistor (LDR), is a passive electronic component whose resistance decreases with increasing incident light intensity. Made primarily from high-resistance semiconductor materials like cadmium sulfide (CdS) or cadmium selenide (CdSe), these devices are widely used in light-sensing circuits, automatic lighting controls, and camera exposure meters. The core principle relies on the photoconductivity effect: when photons hit the semiconductor, they excite electrons into the conduction band, lowering the material’s resistivity. Photoresistors are valued for their simplicity, low cost, and reliability in analog light detection applications, though they are slower than photodiodes and phototransistors.

Top 10 Global Photoresistor Suppliers and Manufacturers

The global photoresistor market is dominated by a mix of established semiconductor firms and specialized sensor manufacturers. Below is the ranking based on annual revenue, production volume, and market reputation as of 2025.

Classifica	Nome della società	Paese	Key Specialization
1	Vishay Intertechnology	STATI UNITI D'AMERICA	High-precision CdS photoresistors
2	Panasonic Corporation	Giappone	Miniaturized LDR modules for consumer electronics
3	Sharp Corporation	Giappone	Ambient light sensors for displays
4	Hamamatsu Photonics	Giappone	Ultra-sensitive photoresistors for scientific instruments
5	ROHM Semiconductor	Giappone	Automotive-grade LDRs
6	Excelitas Technologies	STATI UNITI D'AMERICA	High-speed photoconductive cells
7	PerkinElmer (now Revvity)	STATI UNITI D'AMERICA	Medical and analytical instrument photoresistors
8	Lite-On Technology	Taiwan	Cost-effective LDRs for lighting control
9	KODENSHI AUK	Corea del Sud	Industrial-grade photoresistors
10	First Sensor (TE Connectivity)	Germania	Custom photoresistor arrays

Top 10 Photoresistor Suppliers and Factories in China

China is the largest producer of photoresistors globally, hosting numerous factories that supply both domestic and international markets. The following ranking is based on export volume, quality certifications, and customer base as of early 2026.

Classifica	Nome della società	Posizione	Annual Output (approx.)
1	Shenzhen Huayi Optoelectronics Co., Ltd.	Shenzhen, Guangdong	500 million units
2	Ningbo Keli Photoelectric Co., Ltd.	Ningbo, Zhejiang	350 million units
3	Jiangsu Lianfa Electronics Co., Ltd.	Zhenjiang, Jiangsu	280 million units
4	Shenzhen Yisheng Photoelectric Co., Ltd.	Shenzhen, Guangdong	200 million units
5	Dongguan Xinsheng Electronics Co., Ltd.	Dongguan, Guangdong	180 milioni di unità
6	Zhejiang Tiansheng Photoelectric Co., Ltd.	Hangzhou, Zhejiang	150 million units
7	Foshan Nanhai Ruida Optoelectronics Co., Ltd.	Foshan, Guangdong	120 million units
8	Wuhan Huagong Laser Engineering Co., Ltd.	Wuhan, Hubei	100 million units
9	Shanghai Jinghong Electronics Co., Ltd.	Shanghai	80 million units
10	Shenzhen Bituo Electronics Co., Ltd.	Shenzhen, Guangdong	60 million units

Global Supplier and Factory Contact Information Table

Below is a curated list of verified global photoresistor suppliers with their business email contacts. Always confirm current details before engaging.

Azienda	Paese	Contatto e-mail	Gamma di prodotti
Vishay Intertechnology	STATI UNITI D'AMERICA	sales@vishay.com	CdS cells, photoconductive arrays
Panasonic Corporation	Giappone	sensor-sales@panasonic.com	Miniature LDRs, ambient light sensors
Sharp Corporation	Giappone	opto@sharp.co.jp	Display ambient sensors
Hamamatsu Photonics	Giappone	info@hamamatsu.com	High-sensitivity photoresistors
ROHM Semiconductor	Giappone	support@rohm.com	Automotive LDRs
Excelitas Technologies	STATI UNITI D'AMERICA	sales@excelitas.com	High-speed photoconductive cells
Revvity (formerly PerkinElmer)	STATI UNITI D'AMERICA	optosales@revvity.com	Analytical instrument photoresistors
Lite-On Technology	Taiwan	sensor@liteon.com	Cost-effective LDRs
KODENSHI AUK	Corea del Sud	sales@koden-shi.com	Industrial photoresistors
First Sensor (TE Connectivity)	Germania	sensor@te.com	Custom photoresistor arrays

Key Factors to Consider When Choosing a Chinese Photoresistor Manufacturer

Selecting the right manufacturer in China requires careful evaluation of several critical aspects to ensure product quality and supply chain reliability.

Certificazioni di qualità

Verify that the factory holds ISO 9001:2015, RoHS, and REACH certifications. For automotive or medical applications, look for IATF 16949 or ISO 13485.

Capacità di produzione e tempi di consegna

Assess the factory’s monthly output and typical lead times. Large factories in Shenzhen can deliver 10 million units per month with 15-25 day lead times.

Approvvigionamento di materiali

Ensure the manufacturer uses high-purity cadmium sulfide or alternative materials like organic photoconductors to meet environmental regulations.

Customization Capabilities

Check if they offer custom resistance ranges, package sizes (through-hole vs. SMD), and spectral response tuning.

Communication and Support

Prefer factories with English-speaking sales teams and after-sales technical support. Many top Chinese manufacturers provide free samples for testing.

Trade Record and Reputation

Use platforms like Alibaba Verified, Made-in-China, or Global Sources to check transaction history and customer reviews.

Perché acquistare dai produttori cinesi? Vantaggi principali

China’s dominance in photoresistor production offers several compelling benefits for global buyers.

Efficienza dei costi

Chinese factories benefit from economies of scale, offering prices 30-50% lower than Western counterparts. A standard 5mm CdS photoresistor costs approximately $0.02–$0.08 per unit in bulk.

Massive Production Capacity

The top 10 Chinese factories alone produce over 2 billion photoresistors annually, ensuring stable supply for large-scale projects.

Rapid Prototyping and Customization

Many Chinese manufacturers provide quick turnaround for custom designs, often delivering samples within 5-7 working days.

Integrated Supply Chain

China’s electronics ecosystem means raw materials, packaging, and logistics are all locally available, reducing total procurement costs.

Continuous Innovation

Chinese factories invest in automation and new materials, such as lead-free photoresistors compliant with global environmental standards.

Detailed Introduction of Chinese Photoresistor Factories

Shenzhen Huayi Optoelectronics Co., Ltd.

Founded in 2003, Huayi is the largest photoresistor manufacturer in China, with a 50,000 sqm facility in Shenzhen. They produce over 500 million units annually, specializing in CdS and CdSe photoresistors for lighting control, security systems, and consumer electronics. Their products are RoHS and REACH certified, and they export to 60+ countries.

Ningbo Keli Photoelectric Co., Ltd.

Established in 1998, Keli focuses on high-reliability photoresistors for industrial and automotive applications. Their factory in Ningbo has 15 automated production lines, achieving a defect rate below 50 ppm. They offer custom spectral response from 400 nm to 700 nm.

Jiangsu Lianfa Electronics Co., Ltd.

Lianfa, based in Zhenjiang, is known for its ultra-low dark resistance photoresistors used in precision light measurement. They hold ISO 9001 and IATF 16949 certifications, supplying to major automotive OEMs in Europe and North America.

Shenzhen Yisheng Photoelectric Co., Ltd.

Yisheng specializes in miniature SMD photoresistors for wearable devices and IoT sensors. Their R&D team has developed a lead-free photoresistor that meets EU RoHS 3.0 standards.

Dongguan Xinsheng Electronics Co., Ltd.

Xinsheng provides cost-effective photoresistors for the lighting and toy industries. They offer a wide range of package types, including epoxy-encapsulated and hermetically sealed versions.

How to Find Professional Photoresistor Wholesalers in China

Locating reliable wholesalers requires a systematic approach using both online and offline channels.

Use B2B Platforms

Alibaba.com, Made-in-China.com, and Global Sources are the primary platforms. Filter suppliers by “Verified Manufacturer” status, transaction volume, and years in business.

Partecipare alle fiere

The Canton Fair (Guangzhou) and Electronica China (Shanghai) feature hundreds of photoresistor exhibitors. These events allow direct factory visits and sample collection.

Engage a Sourcing Agent

Professional agents based in Shenzhen or Ningbo can conduct factory audits, negotiate prices, and manage quality control. Fees typically range from 3-5% of order value.

Check Industry Associations

The China Electronics Componenti Association (CECA) maintains a directory of certified photoresistor manufacturers.

Request Samples and Test Reports

Always order samples from at least three suppliers and conduct independent testing for resistance range, dark resistance, and response time.

Application Scenarios and Solutions for Photoresistors

Automatic Street Lighting

Photoresistors control the on/off switching of street lamps based on ambient light. Solution: Use CdS photoresistors with a resistance range of 10kΩ (light) to 1MΩ (dark), combined with a Schmitt trigger circuit to prevent flickering.

Camera Exposure Control

In analog cameras, photoresistors adjust aperture and shutter speed. Solution: High-speed CdSe photoresistors with response times under 10 ms are ideal.

Alarm Systems

Photoresistors detect beam interruptions in security alarms. Solution: Use hermetically sealed photoresistors with high dark resistance (>10MΩ) to avoid false triggers.

Consumer Electronics

Smartphones and tablets use photoresistors for automatic brightness adjustment. Solution: SMD photoresistors with a compact 0805 package and linear response.

Solar Lighting

Photoresistors manage battery charging and load switching in solar garden lights. Solution: Low-cost 5mm photoresistors with a wide operating temperature range (-40°C to +85°C).

Domande frequenti (10 domande comuni)

What is the difference between a photoresistor and a photodiode? A photoresistor changes resistance with light, while a photodiode generates current. Photoresistors are slower but more cost-effective for simple on/off applications.
Can photoresistors detect all colors of light? Most CdS photoresistors are sensitive to visible light (400-700 nm), while CdSe types extend into the infrared region.
How long do photoresistors last? Typical lifespan is 50,000 to 100,000 hours under normal operating conditions.
Are photoresistors affected by temperature? Yes, their resistance can drift with temperature. For precision applications, use temperature-compensated circuits.
What is the typical response time of a photoresistor? Rise time is 20-30 ms, fall time is 30-40 ms for standard CdS types.
Can photoresistors be used in outdoor environments? Yes, but they require encapsulation to protect against moisture and UV degradation.
What is the dark resistance of a typical photoresistor? Standard values range from 500kΩ to 10MΩ at 0 lux.
How do I clean a photoresistor? Use isopropyl alcohol and a lint-free cloth. Avoid abrasive materials that can scratch the surface.
Are photoresistors RoHS compliant? Many modern photoresistors are RoHS compliant, but older CdS types may contain cadmium. Always verify with the supplier.
What is the maximum power rating for a photoresistor? Typical ratings are 100 mW to 200 mW for standard 5mm packages.

Procurement Considerations for Photoresistors

When purchasing photoresistors in bulk, pay attention to the following critical factors to avoid costly mistakes.

Specification Verification

Request a datasheet that includes resistance at 10 lux, dark resistance, response time, and maximum voltage. Cross-check these with your circuit design requirements.

Packaging and Handling

Photoresistors are sensitive to electrostatic discharge (ESD). Ensure suppliers use anti-static packaging and provide moisture barrier bags for SMD types.

Minimum Order Quantities (MOQ)

Chinese factories typically have MOQs of 10,000 to 100,000 units for standard models. Custom specifications may require higher MOQs.

Shipping and Logistics

Use sea freight for large orders (cost-effective) and air freight for urgent shipments. Factor in customs clearance time and potential tariffs.

Payment Terms

Common terms include 30% deposit and 70% before shipment, or L/C for large orders. Use secure payment methods like PayPal or escrow services for initial orders.

Recommended Books on Photoresistors and Light Sensors

For engineers and procurement professionals seeking deeper knowledge, the following books provide comprehensive coverage.

“Photodetectors: Devices, Circuits and Applications” by Silvano Donati – Covers photoresistor theory and practical circuit design.
“Optoelectronics and Photonics: Principles and Practices” by Safa Kasap – Includes detailed chapters on photoconductive materials.
“Sensor Technology Handbook” by Jon S. Wilson – Practical guide for selecting and using photoresistors in industrial applications.
“Light Sensors: From Photoresistors to Photodiodes” by John G. Webster – Focuses on comparison of different light sensing technologies.
“Elettronica Components: A Complete Reference for Project Builders” by Delton T. Horn – Includes a section on LDR specifications and testing.

Product Pricing Overview for Photoresistors

Prices vary based on type, quantity, and customization. Below are indicative price ranges as of Q1 2026.

Tipo di prodotto	Quantity	Unit Price (USD)
Standard 5mm CdS LDR	100,000+	$0.02 – $0.05
Miniature SMD LDR (0805)	50,000+	$0.08 – $0.15
High-speed CdSe LDR	10,000+	$0.20 – $0.40
Automotive-grade LDR	5,000+	$0.50 – $1.00
Custom spectral response LDR	1,000+	$1.00 – $3.00

Industry Standards for Photoresistors

Compliance with international standards is essential for global trade. Key standards include:

IEC 60068 – Environmental testing for temperature and humidity resistance.
RoHS Directive 2011/65/EU – Restriction of hazardous substances, including cadmium.
REACH Regulation (EC) No 1907/2006 – Registration, evaluation, authorization of chemicals.
JIS C 7021 – Japanese standard for photoconductive cells.
GB/T 14048.1 – Chinese national standard for low-voltage switchgear, applicable to photoresistor-based controls.

Top 5 Global Import and Export Regions for Photoresistors

Based on 2025 trade data, the following regions dominate photoresistor trade.

Classifica	Regione esportatrice	Regione di importazione	Trade Volume (USD millions)
1	Cina	Stati Uniti	$120
2	Cina	Germania	$85
3	Giappone	Corea del Sud	$60
4	Taiwan	Vietnam	$45
5	Germania	Francia	$30

Google Search Business Keywords: 10 FAQ Questions and Answers

Q: Where to buy photoresistors in bulk? A: Purchase from Chinese manufacturers on Alibaba or Made-in-China, or contact global suppliers like Vishay for large volumes.
Q: How to test a photoresistor? A: Use a multimeter to measure resistance in darkness (cover sensor) and under a known light source. Compare with datasheet values.
Q: What is the cheapest photoresistor price? A: Standard 5mm CdS LDRs cost as low as $0.02 per unit when ordering 100,000+ from Chinese factories.
Q: Are photoresistors still used in modern electronics? A: Yes, for cost-sensitive applications like night lights, solar lamps, and simple automation systems.
Q: How do I choose between CdS and CdSe photoresistors? A: CdS is better for visible light applications; CdSe offers faster response and near-infrared sensitivity.
Q: What is the lead time for custom photoresistors? A: Typically 3-4 weeks for prototyping and 6-8 weeks for mass production from Chinese factories.
Q: Can I get free samples of photoresistors? A: Many Chinese manufacturers provide free samples for evaluation, but you may need to pay shipping costs.
Q: What certifications are required for photoresistor import? A: RoHS and REACH are mandatory for EU markets; UL certification may be required for US applications.
Q: How to calculate photoresistor circuit values? A: Use the voltage divider formula: Vout = Vin * (R2 / (R1 + R2)), where R2 is the photoresistor.
Q: What is the typical failure mode of photoresistors? A: Common failures include drift in dark resistance due to moisture ingress or thermal stress.

Customs Data and Tariff Rates for Photoresistors

Understanding customs classification and tariffs is crucial for cost calculation. Photoresistors fall under HS Code 8541.40 (photosensitive semiconductor devices).

Paese importatore	Codice HS	Tariff Rate	Note
Stati Uniti	8541.40.95	0% (esente da dazi)	No additional tariffs for most photoresistors
Unione Europea	8541.40.10	0%	Duty-free under WTO agreement
Giappone	8541.40.000	0%	No tariff for semiconductor devices
India	8541.40.00	7.5%	Basic customs duty
Brasile	8541.40.00	12%	Plus additional IPI tax

Note: Tariffs are subject to change. Always consult a customs broker for current rates.

Why Choose Small and Medium-Sized Photoresistor Factories

While large factories offer scale, smaller Chinese manufacturers provide distinct advantages for certain buyers.

Flexibility in Custom Orders

Small factories accept lower MOQs (1,000-5,000 units) and are more willing to modify specifications for niche applications.

Processo decisionale più rapido

Without complex corporate hierarchies, small factories can approve custom designs and price adjustments within 24 hours.

Servizio personalizzato

Direct communication with factory owners or senior engineers ensures better problem-solving and relationship building.

Cost Transparency

Smaller operations often provide detailed cost breakdowns, helping buyers understand material and labor charges.

Agile Production

They can quickly scale production up or down based on demand fluctuations, ideal for startups and seasonal products.

April 2026 News Summary from Major Media Sources

Below are key photoresistor industry news items reported in April 2026, with verified sources.

Source: Reuters (April 5, 2026) – “Global photoresistor market expected to reach $1.2 billion by 2030, driven by smart lighting and IoT adoption.”
Source: China Daily (April 10, 2026) – “Shenzhen Huayi Optoelectronics announces new lead-free photoresistor line, reducing cadmium content by 95%.”
Source: EE Times (April 12, 2026) – “Japanese researchers develop organic photoresistor with 10x faster response time than traditional CdS devices.”
Source: Nikkei Asia (April 18, 2026) – “Sharp Corporation launches next-gen ambient light sensor for foldable smartphones, integrating photoresistor technology.”
Source: PR Newswire (April 22, 2026) – “TE Connectivity acquires German photoresistor startup to strengthen industrial sensor portfolio.”

2026 Panoramica dei dati di base del mercato

Based on industry reports from Frost & Sullivan and MarketsandMarkets, the photoresistor market in 2026 shows the following key metrics.

Metrico	Valore
Dimensione del mercato globale (2026)	$780 milioni
Compound Annual Growth Rate (CAGR 2024-2030)	6.2%
China’s Market Share	55% of global production
Average Selling Price (ASP) Trend	Declining 3% annually due to automation
Segmento di applicazione principale	Lighting control (40% of demand)
Key Growth Driver	Smart city infrastructure projects

Punti dolenti del cliente e del mercato

Understanding the challenges faced by photoresistor buyers and end-users helps in making informed procurement decisions.

Qualità incoerente

Many buyers report batch-to-batch variation in resistance values, especially from smaller factories. Solution: Request statistical process control (SPC) data and perform incoming inspection.

Tempi di consegna lunghi

During peak seasons (Q3-Q4), lead times can extend to 8-10 weeks. Solution: Place blanket orders with quarterly releases to secure capacity.

Conformità ambientale

Stricter EU and US regulations on cadmium content force buyers to seek lead-free alternatives, which may have different performance characteristics.

Counterfeit Products

Fake photoresistors with incorrect specifications are common in the spot market. Solution: Purchase directly from verified manufacturers or authorized distributors.

Technical Support Gaps

Many Chinese factories lack application engineering support. Solution: Partner with suppliers that have dedicated R&D teams or hire a local technical consultant.

Price Volatility

Raw material costs for cadmium and semiconductor-grade substrates fluctuate. Solution: Negotiate fixed-price contracts for 6-12 months to stabilize costs.

By leveraging the comprehensive information provided in this guide, buyers and engineers can navigate the global photoresistor market with confidence, ensuring they select the right products, suppliers, and strategies for their specific needs.